Re: [Rats] Which Asymmetric algorithms for Charra?

Michael Richardson <mcr+ietf@sandelman.ca> Tue, 11 August 2020 23:26 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
To: "Eric Voit \(evoit\)" <evoit=40cisco.com@dmarc.ietf.org>
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Subject: Re: [Rats] Which Asymmetric algorithms for Charra?
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Eric Voit \(evoit\) <evoit=40cisco.com@dmarc.ietf.org> wrote:
    > During the charra presentation at IETF 108, we said we were going to ask the
    > following question to the list: "Should the algorithm set defined in YANG be
    > reduced to just those asymmetric algorithms currently exposed in the current
    > TPM 1.2 and 2 specifications?"

You are asking about *asymmetric* algoritms.
I'd like to see EdDSA in the list, and I suspect that they aren't in the TPM spec.

    > This is reflected seen in
    > https://www.ietf.org/proceedings/108/slides/slides-108-rats-sessb-charra-upd
    > ate-00, Slide 7.

And that slide shows them missing.

    > The proposal I would like to make is as follows:

    > *	The TCG tracked algorithms supportable by a TPM should be the only
    > ones included in a charra maintained list of YANG identities.

You also write:
   2. Identities instead of strings for TCG and IETF crypto algorithm types.
      Strings allow lots of errors to be introduced. (Question #1)

the otherside if you don't use strings is you use an enum, which is not an
IANA registry.  So you need an integer with an IANA registry.

    > *	The YANG model will indicate what TCG algorithms are deprecated by
    > the IETF.  However identities for these deprecated algorithms from the TCG
    > table will be assigned.  (e.g., SHA-1)

Good.

    > Are there any objections/questions/comments on this proposal?    I have a
    > strawman YANG file posted at:

    > https://github.com/ietf-rats-wg/basic-yang-module/compare/master...ericvoit:
    > patch-4

I think you need determine if this is a *TCG TPM* yang module, or if it is
intended to accomodate other technologies.  They might be essentially
proprietary, but for this interface, makes them interoperate.

--
Michael Richardson <mcr+IETF@sandelman.ca>ca>, Sandelman Software Works
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